Modifying Configuration Properties (Classic Layout)

Note: As of Cloudera Manager version 5.2, a new layout of the pages where you configure Cloudera Manager system properties was introduced. In
Cloudera Manager version 5.4, this new layout displays by default. This topic discusses how to configure properties using the older layout, called the "Classic Layout". For instructions on using the
new layout, see Modifying Configuration Properties Using Cloudera Manager.

To switch between the layouts, click either the Switch to the new layout or Switch to the classic layout links in the
upper-right portion of all configuration pages.

When a service is added to Cloudera Manager, either through the installation or upgrade wizard or with the Add Services workflow, Cloudera Manager automatically sets the configuration
properties, based on the needs of the service and characteristics of the cluster in which it will run. These configuration properties include both service-wide configuration properties, as well as
specific properties for each role type associated with the service, managed through role groups. A role group is a set of configuration properties for a role
type, as well as a list of role instances associated with that group. Cloudera Manager automatically creates a default role group named Role
Type Default Group for each role type. See Role Groups.

Changing the Configuration of a Service or Role Instance (Classic Layout)

Go to the service status page.

Click the Configuration tab.

Under the appropriate role group, select the category for the properties you want to change.

To search for a text string (such as "snippet"), in a property, value, or description, enter the text string in the Search box at the top of the category
list.

Moving the cursor over the value cell highlights the cell; click anywhere in the highlighted area to enable editing of the value. Then type the new value in the field provided (or
check or uncheck the box, as appropriate).

To facilitate entering some types of values, you can specify not only the value, but also the units that apply to the value. For example, to enter a setting that specifies bytes per
second, you can choose to enter the value in bytes (B), KiBs, MiBs, or GiBs—selected from a drop-down menu that appears when you edit the value.

If the property allows a list of values, click the icon to the right of the edit field to add an
additional field. An example of this is the HDFS DataNode Data Directory property, which can have a comma-delimited list of directories as its value. To remove an item from such a list, click the
icon to the right of the field you want to remove.

Click Save Changes to commit the changes. You can add a note that will be included with the change in the Configuration History. This will change the
setting for the role group, and will apply to all role instances associated with that role group. Depending on the change you made, you may need to restart the service or roles associated with the
configuration you just changed. Or, you may need to redeploy your client configuration for the service. You should see a message to that effect at the top of the Configuration page, and services will
display an outdated configuration (Restart Needed),(Refresh Needed), or outdated client configuration indicator. Click the indicator to display the Stale Configurations page.

Validation of Configuration Properties

Cloudera Manager validates the values you specify for configuration properties. If you specify a value that is outside the recommended range of values or is invalid, Cloudera Manager
displays a warning at the top of the Configuration tab and in the text box after you click Save Changes. The warning is yellow if the value
is outside the recommended range of values and red if the value is invalid.

Overriding Configuration Properties

For role types that allow multiple instances, each role instance inherits its configuration properties from its associated role group. While role groups provide a convenient way to
provide alternate configuration properties for selected groups of role instances, there may be situations where you want to make a one-off configuration change—for example when a host has
malfunctioned and you want to temporarily reconfigure it. In this case, you can override configuration properties for a specific role instance:

Go to the Status page for the service whose role you want to change.

Click the Instances tab.

Click the role instance you want to change.

Click the Configuration tab.

Change the configuration values as appropriate.

Save your changes.

You will most likely need to restart your service or role to have your configuration changes take effect.

Viewing and Editing Overridden Configuration Properties

To see a list of all role instances that have an override value for a particular configuration setting, go to the entry for the configuration setting in the Status page, expand the
Overridden by n instance(s) link in the value cell for the overridden value.

To view the override values, and change them if appropriate, click the Edit Overrides link. This opens the Edit Overrides page, and
lists the role instances that have override properties for the selected configuration setting.

On the Edit Overrides page, you can do any of the following:

View the list of role instances that have overridden the value specified in the role group. Use the selections on the drop-down menu below the Value
column header to view a list of instances that use the inherited value, instances that use an override value, or all instances. This view is especially useful for finding inconsistent properties in a
cluster. You can also use the Host and Rack text boxes to filter the list.

Change the override value for the role instances to the inherited value from the associated role group. To do so, select the role instances you want to change, choose Inherited Value from the drop-down menu next to Change value of selected instances to and click Apply.

Change the override value for the role instances to a different value. To do so, select the role instances you want to change, choose Other from the
drop-down menu next to Change value of selected instances to. Enter the new value in the text box and then click Apply.

Resetting Configuration Properties to the Default Value

To reset a property back to its default value, click the Reset to the default value link below the text box in the value cell. The default value is inserted
and both the text box and the Reset link disappear. Explicitly setting a configuration to the same value as its default (inherited value) has the same effect as using the Reset
to the default value link.

Restarting Services and Instances after Configuration Changes

If you change the configuration properties after you start a service or instance, you may need to restart the service or instance to have the configuration properties become active. If
you change configuration properties at the service level that affect a particular role only (such as all DataNodes but not the NameNodes), you can restart only that role; you do not need to restart
the entire service. If you changed the configuration for a particular role instance (such as one of four DataNodes), you may need to restart only that instance.

If this documentation includes code, including but not limited to, code examples, Cloudera makes this available to you under the terms of the Apache License, Version 2.0, including any required
notices. A copy of the Apache License Version 2.0 can be found here.